Semi-indirect-lighting fixture.



H. O. ADAM. SEMI-INDIRECT LIGHTING FIXTURE.

APPLIOATION FILED APR. 16, 1914.

Patented Dec. 22, 1914.

HARRY G. ADAM, OF ST. LOUIS, MISSOURI.

SEMI-INDIRECT-LIGHTIHG FIXTURE.

To all whom it may concern:

Be it known that I, HARRY C. ADAM, a citizen of the United States,residing at St. Louis, Missouri, have invented a certain new and usefulImprovement in Semi-Indirect-Lighting Fixtures, of which the followingis a full, clear, and exact description, such as will enable othersskilled in the art to which it appertains to make and use the same.

This invention relates to a semi-indirect lighting fixture of the typein which a translucent shield or bowl is arranged under the lightingunit so as to diffuse the light and reflect the secondary raysupwardlyonto the top reflector, and it is an improvement upon the semi-indirectlighting fixture described in my pending application, Serial No.821,030, filed February 25th, 1914, wherein the top reflector is sodesigned that the secondary rays will be projected downwardly withoutcausing a large volume of the rays to pass through the electric lampbulb. In the fixture described in the application referred to thediffusing shield or bowl that is arranged under the lighting fixture issubstantially semi-spherical in shape, and while said fixture is veryefficient and produces a good light, still, there is a tendency for theindirect rays that are projected downwardly by the top reflector toglance off the diffusing shield, instead of passing directly throughsame, due to the fact that the bottom portion of the shield is curved orapproximately semi-spherical in shape.

The object of. my present invention is to provide a semi-indirectlighting fixture that embodies the good features and characteristics ofthe fixture describedin the application referred to, but Which is animprove ment upon the same in' thattthe difl'using shield or bowl is sodesigned that the indirect rays projected downwardly onto same from thetop reflector will be sure to pass through the bottom portion of theshield without glancing ofl' same at an angle.

Another object is to provide a semi-indirect lighting fixture of thegeneral type mentioned, in which the diffusingv shield or bowl is sodesigned that a large portion of the direct rays from the lighting unitthat 1 strike the sides of the bowl will be projected downwardly throughthe bottom portion of the bowl.

Other objects and desirable features of Specification of Letters Patent.

Patented Dec. 22, 19M.

Application filed April 16, 914. erial No. 832,224..

trating a slight modification of my invention.

Referring to Fig. 1 of the drawings which illustrates one form of myinvention, A designates the top reflector of the fixture and Bdesignates the inverted bowl or diffusing shield that is arranged underthe lighting unit, which preferably consists of an electric light bulbC, the top reflector and diffusing shield being of any preferred shapein outline. The top reflector A can be formed from any suitablematerial, and it can either be provided with a plain edge or a flangededge, the reflector A herein shown being provided at its outer edge witha verticallydisposed flange 1 whose upper edge bears against theceiling, as shown in Fig. 1. Adjacent the outer edge of the topreflector A is a reflecting surface at which is inclined upwardly fromthe outer edge of the reflector, and adjacent the center of thereflector is an oppositely inclined reflecting surface y, saidreflecting surfaces preferably merging into each other. While I preferto form the reflecting surfaces :2 and y straight or plain in transversecross section. as shown in the drawings, so that they will form refleeting planes, they could, of course, be curved slightly in transversecross section without departing from the spirit of my invention.Therefore, I do not wish it to be understood that my invention islimited to a semi-indirect lighting fixture in which the top reflectoris provided withreflecting surfaces as and y of the particular angle andshape herein shown. It is essential, however, 'that the reflectingsurfaces a; and y be disposed at a slight angle to each other and alsowith relation to a horizontal plane in order to obtain-the results whichI claim my improved fixture accomplishes, but the general form oroutline of said reflecting planes as an entirety is immaterial, so faras my bread idea is concerned. The upper edge of the diffusing shield ortranslucent bowl B preferably terminates at a point above the filamentvf of the electric light bulb C soas to prevent any rays from escapingover the upper edge of said shield without striking against the topreflector A. In view of the fact that the reflecting surface a: inclinesupwardly from a horizontal plane the direct rays that strike againstsame will be projected downwardly and also outwardly, thus causing thelight to be concentrated instead of being thrown across the room inplanes approximately parallel to the ceiling of the room. The secondaryrays y that strike against the upper edge portion of the shield B, arereflected onto the reflecting surface 3 of the top reflector A and arethence projected downwardly in substantially straight lines, asindicated by the broken lines 1 without striking or passing through thelamp bulb C. Consequently there is very little loss of light with myimproved fixture when the lamp bulb becomes blackened with age, owing tothe fact that the top reflector is providedwith areflecting surfacewhich is so disposed that a large volume of the secondary rays which arereflected onto same from the diffusing shield, will be projecteddownwardly without passing through the lamp bulb. Moreover, there is nohorizontal glare between the top reflector and the diffusing shield, forsaid shield is so proportioned and is so positioned with relation to thetop reflector, that none of the direct rays can escape without passingthrough the shield or striking against the top reflector. In the fixtureherein shown the angularly disposed surface fl/ of the top reflectorextends downwardly to the socket of the lamp so as to serve as areflecting surface for the secondary rays that concentrate at the centerof the top reflector. In order to reduce the tendency of the rays thatare projected downwardly from the angularly disposed surface 4 of thetop reflector to glance oil the diffusing shield or bowl, intead ofpassing directly through same, I havenrovided said bowl with a flat, orsubstantially flat, bottom portion 2 that is disposed at approximatelyright angles to the indirect rays that are projected down wardly by thereflecting surface 00 of the top reflector, consequently, said ravs willstrike the bottom portion 2 of the diffusing shield B and ass directlythrough same Without glancing off into the interior of the bowl.

The sides of the bowl or shield B can either flare gradually from thebottom to the top of the bowl, as shown in Fig. 2, or the sides of thebowl can flare in opposite directions from approximately the horizontalcenter of the bowl, as shown in Fig. 1. y forming the bowl in thismanner, namely, providing the side walls of same with two oppositelyflared portions 3 and 4, as shown in Fig. 1, I obtain a reflectingsurface 3 at the upper portion of the bowl. which causes the secondaryrays 2 from the lighting unit to be reflected upwardly onto thereflecting surface y of the top reflector, and I obtain a reflectingsurface 4 at the lower portion of the bowl, which causes the direct rays.2 from the lighting unit to be reflected downwardly onto the bottom 2of the bowl. In a bowl of the form shown in Fig. 2 the bottom 2 of thebowl can be plain or smooth, but when the bowl is provided with a sidewall which flares in opposite directions, as shown in Fig. 1, it ispreferable to provide the bottom 2 of the bowl with projections whichare so disposed with relation to the rays of light that are projectedonto same from the reflecting surface 4 of the side wall that said rayswill pass downwardly through the bottom of the bowl. In the form of myinvention shown in Fig. l the bottom of the bowl is corrugated, orprovided with a plurality of concentric annular shaped projections 5,but I do not wish it to be understood that it is essential that thebottom of the bowl be formed in this manner, for the same result can beaccomplished in various other ways without departing from the spirit ofmy invention.

In a semi-indirect lighting fixture of the character described thesecondary rays that are reflected downwardly from the top reflector willnot strike or pass through the lamp bulb, and said rays will passdirectly through the diffusing shield or bowl, instead of glancing offsame, owing to the fact that the bottom of said bowl is disposed atapproximately right angles to the path of said rays. Furthermore, whenthe side walls of the bowl are provided with oppositely flaredreflecting surfaces that are disposed at an angle with relation to eachother, as shown in Fig. 1, the direct rays from the lighting unit thatstrike the refleeting surface 4 of the bowl will be projected downwardlythrough the bottom 2 of the bowl.

It is immaterial, so far as my broad idea is concerned, how the bowl orshield is supported. It can either be suspended from the top reflectorby means of chains or other members 6 that are connected to the devicesf3 secured to the side walls of the shield adacent the upper edge ofsame, or it can be .suspended from the top reflector by means of rods 7whose lower ends are secured to a device 8 that is connected to thebottom 2 of the bowl, as shown in Fig. 1.

Having thus described my invention, what I claim is:

l. A semi-indirect lighting fixture, comprismg a top reflector and adiffusing shield arranged above and below the lighting unit,respectively, saidtop reflector being provlded with angularly disposedreflecting surfaces consisting of planes that are inclined in oppositedirections to each other, said slneld having a substantially flat bottomthat hes 1n approximately a horizontal plane, and side walls whose upperportions flare outwardly away from the lighting unit.

2. A semi-indirect lighting fixture, comprising a top reflector and adiflusing shield arranged above and below the lighting unit,respectively, and consisting of separate and distinct members that arespaced away from each other, said top reflector being provided adjacentits outer edge with a reflecting surface which inclines upwardly andadjacent its center with an oppositely inclined reflecting surface, andsaid shield being of less diameter than said top reflector and providedwith a substantially. flat bottom that lies in an approximatelyhorizontal plane.

3. A semi-indirect lighting fixture, comprising a top reflector providedadjacent its center with a reflecting surface consisting of a plane thatinclines upwardly from the lighting unit, and a diffusing shieldsurrounding the lighting unit and provided with a horizontally dlsposedportion and a flared upper portion that causes secondary rays from thelighting unit to be reflected onto the inclined reflecting surface ofthe top reflector.

4. A semi-indirect lighting fixture, comprising a top reflector providedadjacent the center of same with a reflecting surface consisting of aplane that inclines upwardly from the lighting unit toward the outeredge of the reflector, and a diffusing shield surrounding the lightingunit and provided with a substantially flat bottom and upright sidewalls that'are flared in opposite dlrections from a point intermediatethe upper and lower end-of the shield.

5. A semi-indirect lighting fixture, comprising a top reflector providedadjacent the center of same with a reflecting surface that inclinesupwardly from the lighting unit toward the outer edge of the reflector,

and a diffusing shield surrounding the lighting unit and provided withsubstantially flat bottom and side walls whose lower portions flareoutwardly from a point intermediate the upper and lower ends of theshield, thereby causing some of the direct rays from the lighting unitwhich strike said flared portion to be projected inwardly and downwardlyonto the bottom of the shield.

6. A semi-indirect lighting fixture, comprising a top reflector providedwith a reflecting surface that inclines upwardly from the center towardthe outer edge of the reflector, and a bowl-shaped diffusing shieldsurrounding the lighting unit and spaced away from said top reflector,said shield being provided with side walls whose upper and lowerportions flare in opposite directions from a point intermediate theupper and lower ends of the shield.

7. A semi-indirect lighting fixture, comprising a top reflector providedwith a reflecting surface that inclines upwardly from the center towardthe outer edge of the reflector, and a bowl-shaped difl'using shieldsurrounding the lighting unit and provided with side walls whose upperand lower portions flare in opposite directions, said shield having asubstantially flat bottom that is provided with projections forintercepting the direct rays that are projected onto same from the lowerportion of the side walls of the shield.

In testimony whereof I hereunto afiix my signature in the presence oftwo witnesses, this tenth day of April 1914:.

HARRY C. ADAM.

Witnesses:

WELLS L. Cannon, Jnssm CLARK.

